The Relation Between Sexual Orientation and Penile Size

Abstract

The relation between sexual orientation andpenile dimensions in a large sample of men was studied.Subjects were 5122 men interviewed by the KinseyInstitute for Research in Sex, Gender, and Reproduction from 1938 to 1963. They were dichotomouslyclassified as either homosexual (n = 935) orheterosexual (n = 4187). Penile dimensions were assessedusing five measures of penile length and circumferencefrom Kinsey's original protocol. On all fivemeasures, homosexual men reported larger penises thandid heterosexual men. Explanations for these differencesare discussed, including the possibility that these findings provide additional evidence thatvariations in prenatal hormonal levels (or otherbiological mechanisms affecting reproductive structures)affect sexual orientation development.